Safety control for automatic carwash pump

ABSTRACT

A safety control system which is operable to shut off the pump and other carwash equipment in the event that the supply of water to the pump is depleted below a predetermined level. The carwash is interrupted in midcycle and provision is made for completing the cycle even though the car may in the meantime have departed while the system was inoperative.

D United States Patent [111 3,570,5

[72] Inventors Lois G- Dale [56] References Cited '31 321 N 24 h 8UNITED STATES PATENTS f' 3,097,499 7/1963 Rodgers 137/399x 63565 3 400725 9/1968 Miller et al 134/57 [21] Appl. No. 806,611 [22] Filed Mar.12, 1969 Primary Examiner-Price C. F aw, Jr. [45] Patented Mar. 16, 1971Attorney-Scofield, Kokjer, Scofield and Lowe [54] SAFETY CONTROL FORAUTOMATIC CARWASH PUMP zchims 1 Drawing ABSTRACT: A safety controlsystem which is operable to [52] U.S. Cl. 134/45, shut off the pump andother carwash equipment in the event 134/57, 137/399 that the supply ofwater to the pump is depleted below a [51] Int. Cl B60s 3/04, pr m nlevelh earwash i in errupted in midcycle B08]; 3/02 and provision ismade for completing the cycle even though [50] Field of Search 134/57,45, the car may in the meantime have departed while the system 58, 123;137/399 was inoperative.

3 SAFETY CONTROL FOR AUTOMATIQ CARWASH PUMP BACKGROUND AND SUMMARY OFTHE INVENTION Automatic carwashes are, for the large part, untended. Theassumption is made that water will always be available from the watersupply system for the community in which the carwash is located.However, from time to time, at develops that the supply is shutoff orbecomes sufficiently inhibited that the pump is starved. In suchsituations, and with the high-pressure pumps that are utilized for suchsystems, the pumps can be seriously damaged if they run for even a fewminutes without adequate water to the intake.

One of the main objects of the present invention is to provide means forcontinuously maintaining surveillance over and sensing the depletion ofwater to the point where pump starvation is imminent and in response tothis condition operating to shut the system down until the wateravailability is such as to permit continuation of the washing operation.The continuation of the washing operation, once interrupted, isaccomplished without regard to whether or not an automobile has stayedin position in the carwash. The system is thus fully automatic and thuscan be utilized successfully on an around the clock basis and in remotelocations. v

Other objects and features of the invention, together with the featuresof novelty appurtenant thereto, will appear in the course of thefollowing description.

In the accompanying drawing, the single FIG. comprises a partlyschematic and partly diagrammatic illustration of a typical pumping andelectrical system for automatic carwash which embodies a preferred formof our invention.

In illustrating the invention, we have chosen to show in schematic formwhat is a typical and rudimentary electrical system for an automaticcarwash. Reference numeral indicates a coin receptacle which is designedto receive coins and, upon reception of the proper amount, to conditionthe program timer to start upon completion of the circuit in the system.Power lines L1, L2 are the power source for the system. A master switch12 is normally closed to prepare the unit for operation. Conductors 1'3,14 lead to the high-pressure pump for the system and conductors 15, 15ato a spray carriage (not shown). There are, of course, various types ofspray carriages on the market and known to the art, most of which areelectrically operated. However, the spray carriage itself does not playany part in the present invention and further detail is not believednecessary to an understanding of the invention.

There are two additional switches in the circuit which operate toinitiate the pumping and spray carriage operation. Switch I6 is whatwill be denoted as a position switch. Switch 17 is a manual controlswitch. Switch 16 is connected in series with the master switch 12 andlocated within the bay of the carwash (not shown). It is biased normallyopen. Switch 16 is positioned to sense the movement of a car intowashing position within the installation. When the car reaches washingposition, the tire or some other part of the car operates to closeswitch 16 and, as will be evident, this completes the circuit throughthe system, thus starting the timer and energizing the pump and spraycarriage. Switch 17 is a manual switch which is normally open but can beclosed to start the carwash with the timer the same as the positionswitch 16, as it is merely a bypass switch for position switch 16.

The water for the carwash system is stored in a storage tank 18. Thistank is fed from a conventional water supply system (not shown) whichdelivers water to the storage tank through the line 19. Discharge fromline 19 to thetank is controlled by means of a valve 2% operated by afloat 21. Float 21 operates to close off the supply to the tank when itrises a predetermined upper level. In the drawing, the tank is shownwith the water level 22 just at the point beyond which further recessionin the level will operate the automatic shutoff mechanism, now to bedescribed.

Supported within the tank are two floats 23 and 24, each of which ismounted on an upright float rod 25 and 26, respectively. The float rodsare supportedfor free up and down movement by U-shaped support brackets27 and 28, each of which is provided with upper and lower arms, 27a,27b, 23a, 28b, suitably apertured to support the rods in'a slidingrelationship. The upright portions of the brackets 27. 28 arerespectively welded or otherwise fastened to the tank or other support.

The float rod 25 carries two collars or lugs 25a and 25b which arespaced longitudinally from one another along the rod. The rod 26 carriesa similar set of lugs or collars 26a, 26b, and for reasons which willsubsequently be explained, while the upper collars are preferably at thesame level on the two rods, the lower collar 26b on rod 26 is positionedat a lower level than the corresponding collar 25b on rod 25.

The collars or the lugs on the float rods are designed to operate theoperating members of on-off sump type switches 29 and 30 that operatewith either weights or floats (such as Sumptrol switches manufactured bythe Square D Corporation). The switch 29 is connected in series in lineL1. Switch 30 is connected in parallel with the position switch 16 andmanual switch 17. The switches are mounted on a junction box 31 which inturn is supported by a beam or bar 32 bridging the top.

In the condition illustrated in the drawing, switch 29 is in the circuitclosing ("closed") condition, while switch 30 is in the circuitinterrupting (open) condition. Movement of the floats 23, 24 and therods carried thereby further downward will result in a changing of thecondition of both switches 29 and 30, switch 29 being altered to opencondition, while switch 30 is closed. These conditions will stay thesame until the lower collars 25b, 2612 move upwardly beside the switchesand shift the Sumptrol arms, thus shifting the switches back to theinitial or starting condition.

The program timer and coin receptacle in the illustrated embodiment areof the type in which once coins have been deposited and the cycle iscommenced, further deposit of coins is possible whether the wash cycleis completed or not as long as switch 29 is closed. Coins may not bedeposited when switch 29 is open as they will be rejected. The coin box,as well as the carwash, is inactive as long as switch 29 is open.

In the normal operation of our system, before a car enters the bay, thetank 18 would, of course, normally be full, with the level of the waterup to the point where the float 21 has operated its valve 20 to shut offthe supply. In this condition'of the tank, and as earlier indicated,switch 29 is in the closed condition, while switch 30 is in the opencondition. Floats 23 and 24 will be in their raised positions, the uppercollars 25a, 26a bearing against the stops provided by the bracket legs27a and 28a, and with the lower collars 25b and 26b just past the uppermidpoint of the Sumptrol switches.

Under normal circumstances, the pump operates to remove water from thetank about as fast as it is supplied from the incoming supply. Thisassumes that the supply is under normal pressure and that there is nointerference with the supply. Thus, once the unit is started, the waterlevel will decrease until float valve 20 isopened and if the systemremains normal, the level will not fall very far.

The unit is started, of course, by inserting coins in the coin collectorand by moving the automobile or other vehicle into the carwash until theposition switch 16 is closed. Once the position switch is closed, theparts of the system areenergized the pump begins to draw water from thetank.

In the event that the supply decreases, the level in tank 18 will beprogressively lowered and eventually the level will reach the pointillustrated. As the level recedes even further, the upper collars 25a,26a will contactand move the toggles of the switches 29 and 30 throughto operate the switches, shifting switch 29 to the open position andswitch 30 to the closed position.

The opening of switch 29 shuts off the circuit to the entire system,even though the car remains in position in the wash with position switch116 closed. As earlier not'ed, if the coin box is of the type which isautomatically blocked during the cycle, it cannot receive any coins.Even if it did, the system would remain off. The pump is, of course, cutoff when the system is cut off as is the spray carriage and the systemremains quiescent until such time the water returns to a level in whichthe collar 25b on the float rod 25 serves to close switch 29.

It has been earlier noted that the disposition of collar 26b on rod 26is such that with the floats rising at the same level and beingsupported on the liquid, switch 29 will be closed before collar 26breaches its switch 30. This has the effect of molesing the circuit tothe system and pumping will once again commence, as will operation ofthe spray carriage. The timer program will be resumed.

The purpose of switch 30 is to insure that the system will be set inoperation by closing of switch 29, even though in the interim a car hasdriven off of the position switch 16. The float switch 30, remaining inthe closed position and being in parallel with the position switch,insures that once the float switch 29 has been closed, the system isoperative. Thus, the cycle will be finished automatically and the systemreset for operation upon deposit of additional coins and entry ofanother vehicle into the bay.

As earlier noted, the pump withdraws liquid from the tank at about thesame rate that it is supplied from the supply tank. Accordingly, thelevel remains fairly constant in tank 18 during pumping Once the pumpcuts off at the end of the cycle, the level will rise and float 24 willbe carried upward and its lower collar 26b will reopenthe switch 30. Theentire system is thus ready for another cycle of operation.

From the foregoing, it will be seen that this invention is one welladapted to attain all of the ends and objects hereinabove set forth,together with other advantages which are obvious and which are inherentto the structure.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsubcombinations. This is contemplated by and is within the scope of theclaims.

As many possible embodiments may be made of the invention withoutdeparting from the scope thereof, it is to be understood that all matterherein set forth or shown in the accompanying drawing is to beinterpreted as illustrative and not in a limiting sense.

We claim:

1. In an automatic carwash installation, the combination of:

a liquid storage tank;

a carwash mechanism including an electrically powered pump connectedwith said tank for drawing liquid therefrom;

a source of supply for replenishing the tank;

an electric circuit for said carwash mechanism;

programming means connected into said circuit for establishing a cycleof operation of said washing mechanism which continues so long as thecircuit remains closed;

means for initiating the cycle;

water level sensing means for said tank;

first switch means connected with said circuit and con trolled by saidlevel sensing means and operable to open said circuit and interrupt saidcycle in response to said sensing means when the water level falls belowa preselected minimum level and to reclose said circuit upon return ofthe level to a preselected satisfactory operation level;

position switch means in said circuit operable to open said circuit if acar leaves the wash position; and

second switch means connected in said circuit in parallel with saidposition switch means and controlled by said level sensing means andoperable to close in response to said level sensing means when saidminimum level is reached and to open upon return of the level to aselected level above said satisfactory operation level whereby to permitcompletion of the operating cycle without a car being in wash ositiop, I2. The combination as in clalm 1, wherein said level sensing meansincludes a pair of floats and switch operating members connected withthe respective floats, each of said floats operable to control one ofsaid switch means.

1. In an automatic carwash installation, the combination of: a liquidstorage tank; a carwash mechanism including an electrically powered pumpconnected with said Tank for drawing liquid therefrom; a source ofsupply for replenishing the tank; an electric circuit for said carwashmechanism; programming means connected into said circuit forestablishing a cycle of operation of said washing mechanism whichcontinues so long as the circuit remains closed; means for initiatingthe cycle; water level sensing means for said tank; first switch meansconnected with said circuit and controlled by said level sensing meansand operable to open said circuit and interrupt said cycle in responseto said sensing means when the water level falls below a preselectedminimum level and to reclose said circuit upon return of the level to apreselected satisfactory operation level; position switch means in saidcircuit operable to open said circuit if a car leaves the wash position;and second switch means connected in said circuit in parallel with saidposition switch means and controlled by said level sensing means andoperable to close in response to said level sensing means when saidminimum level is reached and to open upon return of the level to aselected level above said satisfactory operation level whereby to permitcompletion of the operating cycle without a car being in wash position.2. The combination as in claim 1, wherein said level sensing meansincludes a pair of floats and switch operating members connected withthe respective floats, each of said floats operable to control one ofsaid switch means.